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1.
Studies on the bacterial predation rate by rumen protozoa were carried out under laboratory conditions using a technique of fluorescence-labeled bacteria （FLB）. Four Xuhuai goats were used in this experiment to obtain rumen protozoa and bacteria. Two groups were designed as follows： One group was the whole bacteria which were labeled using fluorescence through removing free bacteria from rumen fluid （WFLB）; the other group was the bacteria which were labeled using fluorescence without removing free bacteria from rumen fluid （FLB）. The result indicated that the bacterial predation rates of rumen protozoa was 398.4 cells/（cell h） for the group WFLB, 230.4 cells/（cell h） for the group FLB, when the corresponding values expressed as bacteria-N, they were 2.15 pg N/（cell h） for the group WFLB, and 1.24 pg N/（cell h） for the group FLB, respectively. Extrapolating the assimilation quantity of nitrogen by ciliates on bacteria of Xuhuai goat, there were 103.2 mg N/（d capita） for the group WFLB, and 59.5 mg N/（d capita） for the group FLB, respectively. It was estimated that protein losses due to microbial recycling were 0.645 g pro/（d capita） for the group WFLB and 0.372 g pro/（d capita） for the group FLB, respectively. In addition, the fluorescence-labeled technique would be a potential assay for the determination of bacterial predation rate by rumen protozoa. 相似文献
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[Objective] The study aimed to establish a fast and accurate method to detect the polymorphism of the 12th exon of equine MxA gene. [Method] The 12th exon of MxA gene was amplified by mismatch PCR and the products were analyzed by restriction fragment length polymorphism (RFLP) to determine the point mutation at the 1 790 nt of MxA cDNA. The sequence of the PCR products was also analyzed. [Result] There were three genotypes (AA, AB and BB) in the 12th exon of equine MxA gene; the 2 081 nt of MxA cDNA mutated from G to C, correspondingly changing the 562th amino acid of the coding region of MxA protein from tryptophan to cysteine; the specific sequence of the PCR products amplified by mismatch PCR-RFLP was consistent with the analysis results of RFLP. [Conclusion] The mismatch PCR-RFLP was an easy method with accurate results to detect the polymorphism of the 12th exon of equine MxA gene. 相似文献
3.
Growth performance and rumen microorganism differ between segregated weaning lambs and grazing lambs
JI Shou-kun JIANG Cheng-gang LI Rui DIAO Qi-yu TU Yan ZHANG Nai-feng SI Bing-wen 《中国农业科学(英文版)》2016,(4):872-878
Two feeding patterns of the segregated weaning or grazing in the pasture are carried out worldwide in animal production.To investigate the difference of growth performance and rumen microorganism population related to methane metabolism in the two feeding patterns,three groups of lambs(70 in total)were used:Weaning at 21 days old and being subjected to high-concentration diets(3WK group with 20 lambs),weaning at 35 days old and being subjected to high-concentration diets(5WK group with 20 lambs),or grazing at pasture with the nursing mother(Grazing group with 30 lambs).The growth performance,pH value of rumen content,and the rumen microbes were investigated during weaning period and fattening period with approximately 3 months.Our results showed that lambs in 3WK and 5WK groups demonstrated a better growth performance than the lambs in Grazing group,but no significant difference was observed in the pH value between the three groups(P>0.05).The total rumen bacterial population of the Grazing lambs was significantly lower than that of3WK lambs(P<0.05)and 5WK lambs(P<0.05);however,the population of methanogens was 4.2-and 2.7-fold lower in the3WK(P<0.05)and 5WK(P<0.05)lambs compared with Grazing lambs,respectively;protozoa were also 3.5-and 3.4-fold lower in the 3WK(P<0.05)and 5WK(P<0.05)lambs,respectively.The results revealed that segregated weaning lambs may have better growth performance,and reduce methane-producing microbes. 相似文献
4.
ZHANG Yu-ling LIU Feng-jun ZHANG Jing-jing ZHANG Yong 《农业科学与技术》2009,10(6):23-25,32
[Objective]The aim of this study was to explore the technical system of induced expression in vitro of goat mammary gland epithelial cell,and evaluate expression efficiency of mammary gland specific vector and foreign protein at the cell level.[Method]Goat mammary gland epithelial cell transfected by human lactoferrin gene was inducted by culturing in DMEM/F12 medium supplemented with 5 mg/L insulin,5 mg/L prolactin and 1 mg/L hydrocortisone.Supernatant was collected per 6 hours and concentrated.Expression situation of foreign protein were detected by SDS-PAGE and Western blotting.[Result]There was target protein expression in the induced culture medium,which molecular weight was about 42 kD.[Conclusion]The method used in this study can induce goat mammary gland epithelial cell to express foreign gene,it lays a foundation for researching heterologous expression of foreign gene and producing mammary gland bioreactor. 相似文献
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LI Yu-jie ZHU Yan ZHAO Jian-ning LI Gang WANG Hui LAI Xin YANG Dian-lin 《中国农业科学(英文版)》2014,(3):624-634
This study was aimed to evaluate the potential effects of rest grazing on organic carbon storage in Stipa grandis steppe of Inner Mongolia, China. Using potassium dichromate heating method, we analyzed the organic carbon storage of plant and soil in Stipa grand＆ steppe after rest grazing for 3, 6, and 9 yr. The results indicated that as the rest grazing ages prolonged, the biomass of aboveground parts, litter and belowground plant parts （roots） of the plant communities all increased, meanwhile the C content of the biomass increased with the rest grazing ages prolonging. For RG0, RG3a, RG6a, and RG9a, C storage in aboveground vegetation were 60.7, 76.9, 82.8 and 122.2 g C m2, respectively; C storage of litter were 5.1, 5.8, 20.4 and 25.5 g C m^-2, respectively; C storage of belowground roots （0-100 cm） were 475.2, 663.0, 1 115.0 and 1 867.3 g C m^-2, respectively; C storage in 0-100 cm soil were 13.97, 15.76, 18.60 and 32.41 kg C m^-2, respectively. As the rest grazing ages prolonged, the organic C storage in plant communities and soil increased. The C storage ofbelowground roots and soil organic C was mainly concentrated in 0-40 cm soil body. The increased soil organic C for RG3a accounted for 89.8% of the increased carbon in vegetation-soil system, 87.2% for RG6a, and 92.6% for RG9a. From the perspective of C sequestration cost, total cost for RG3a, RG6,, and RG9a were 2 903.4, 5 806.8 and 8 710.2 CNY haq, respectively. The cost reduced with the extension of rest grazing ages, 0.15 CNY kg^-1 C for RG3a, 0.11 CNY kg-~ C for RG6a and 0.04 CNY kg℃ for RG9a. From the growth characteristics of grassland plants, the spring was one of the two avoided grazing periods, timely rest grazing could effectively restore and update grassland vegetation, and was beneficial to the sustainable use of grassland. Organic C storage for RG9a was the highest, while the cost of C sequestration was the lowest. Therefore, spring rest grazing should be encouraged because it was proved to be a very efficient grassland use pattern. 相似文献
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“胰岛素-转铁蛋白-硒钠”对山羊卵母细胞体外成熟及胚胎发育的影响(英文) 总被引：8，自引：2，他引：6
[Objective] The research aimed to enhance culture efficiencies of oocyte and embryo of goat in vitro and to explore serum-free culture system in vitro.[Method] At present,the conventional solutions of oocyte maturation and embryo development in vitro were always added into 1% ITS(Insulin-transferrin-selenium) or using 1% ITS to replace FBS in 2 kinds culture solutions for conducting in vitro cultures of goat oocyte and parthenogenetic embryo.The influences of ITS on their developments were detected.[Result] ITS in maturation liquid of oocytes could not increase oocytes maturation rate but significantly increased blastocyst rate (58.06% vs. 48.19%)of parthenogenetic embryo.If FBS in maturation liquid of oocytes was replaced by ITS, the maturation rate, cleavage rate and blastocyst rate were basically unchanged.Adding ITS into embryo medium could increase blastocyst rate (68.30% vs. 56.82%)of parthenogenetic embryo of goat.If FBS in embryo medium was replaced by ITS,the cleavage rate didn’t change basically,while the blastocyst rate in ITS was obviously lower than that in FBS group(42.33% vs.56.82%).[Conclusion] ITS could promote maturation of oocyte in vitro and early embryonic development, in addition,ITS could replace serum in maturation medium of oocyte as serum-free culture system for conducting relevant researches. 相似文献
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Li Yan-fang Wang Lei Liang Zi-chao Zhang Mei-mei Wang Jing-jing Liu Da-sen 《东北农业大学学报(英文版)》2018,(1):40-46
Twenty-nine facultative anaerobic cellulose-degrading bacteria were isolated from soil, rumen fluid, rumen residues and diet of dairy cow. Based on 16 Sr DNA analysis by BLAST algorithm method, the results showed that most of the strains were Bacillus genera, and six of the 29 strains were bigger than 10 mm of diameter of clear zones. For them, two strains were isolated from rumen fluid(L5 and L7) and other two were isolated from rumen residue(N5 and N9), while others were isolated from soil(T1) and diet(S6), respectively. Strains from rumen fluid and residue had higher activities of FPCase and CMCase, but lower β-glucosidases. 相似文献
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《（《农业科学与技术》）编辑部》2008,(4)
[Objective] The aim of this study is to understand the effects of donor cell type,embryo stage,number and transfer position on the efficiency of goat transgenic clone.[Method] Using somatic cell nuclear transfer technology,the single goat fetal fibroblasts(GFF)and mammary gland epithelial cells(GMGE)harboring human lactoferrin(hLF)gene were transferred to the enucleated oocyte.Reconstructed karyoplast-cytoplast couplets were fused,activated,and cultured in vitro.Embryos at 2-8 cell stage were transferred into oviduct of synchronized recipients,and blastocysts were transferred into uterine horn.[Result] The pregnancy rate was similar between GFF and GMGE(oviduct transfer:26.47% vs.20.00%),and between oviduct transfer and uterine horn transfer(26.47% vs.25.00%)for GFF group;pregnancy rate in the group with the mean number of embryo transferred per recipient of 21.2 was significantly higher than in those the 5.93 group and 9.64 group(40.00% vs.26.67% and 21.43%).[Conclusion] These results indicate that pregnancy rate of goat transgenic clone couldn't be affected by donor cell type,embryo stage and transfer position but be done by the number of embryo transferred per recipient.In addition,the study also suggests the feasibility of making transgenic goat using GMGE as donor cells. 相似文献
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LIU Feng-jun ZHANG Yu-ling YANG Zi-jun CHEN Xing-qi SUN Da-quan WANG Guo-hua ZHANG Yong .College of Animal Science Technology Henan University of Science Technology Luoyang 《（《农业科学与技术》）编辑部》2008,(4)
[Objective] The aim of this study is to understand the effects of donor cell type,embryo stage,number and transfer position on the efficiency of goat transgenic clone.[Method] Using somatic cell nuclear transfer technology,the single goat fetal fibroblasts(GFF)and mammary gland epithelial cells(GMGE)harboring human lactoferrin(hLF)gene were transferred to the enucleated oocyte.Reconstructed karyoplast-cytoplast couplets were fused,activated,and cultured in vitro.Embryos at 2-8 cell stage were transferred into oviduct of synchronized recipients,and blastocysts were transferred into uterine horn.[Result] The pregnancy rate was similar between GFF and GMGE(oviduct transfer:26.47% vs.20.00%),and between oviduct transfer and uterine horn transfer(26.47% vs.25.00%)for GFF group;pregnancy rate in the group with the mean number of embryo transferred per recipient of 21.2 was significantly higher than in those the 5.93 group and 9.64 group(40.00% vs.26.67% and 21.43%).[Conclusion] These results indicate that pregnancy rate of goat transgenic clone couldn't be affected by donor cell type,embryo stage and transfer position but be done by the number of embryo transferred per recipient.In addition,the study also suggests the feasibility of making transgenic goat using GMGE as donor cells. 相似文献
10.
《农业科学学报》2017,(10)
Anthropogenic activities profoundly influence carbon sequestration in the Eurasian Steppe. In particular,grazing has been identified as having a major effect on carbon sequestration. However,the extent to which grazing affects regional patterns or carbon sequestration is unknown. In this study,we evaluated the impact of regional grazing on grassland carbon sequestration using the Boreal Ecosystem Productivity Simulator(BEPS) and the Shiyomi grazing model. Model performances were validated against the results from field measurements and eddy covariance(EC) sites. Model outputs showed that in 2008,the regional net primary productivity(NPP) was 79.5 g Cm~(–2),and the net ecosystem productivity(NEP) was –6.5 g Cm~(–2),characterizing the region as a weak carbon source. The Mongol Steppe(MS) was identified as a carbon sink,whereas the Kazakh Steppe(KS) was either carbon neutral or a weak carbon source. The spatial patterns of grazing density are divergent between the MS and the KS. In the MS,livestock was mainly distributed in China with relatively good management,while in the KS livestock was mainly concentrated in the southern countries(especially Uzbekistan and Turkmenistan) with harsh environments and poor management. The consumption percentages of NPP in Turkmenistan,Tajikistan and Uzbekistan were 5.3,3.3 and 1.2%,respectively,whereas the percentages in other countries were lower than 1%. Correspondingly,grazing consumption contributed to the carbon sources of Turkmenistan,Tajikistan and Uzbekistan by 11.6,6.3 and 4.3%,respectively,while it weakened the carbon sink in Inner Mongolia,China and Mongolia by 1.6 and 0.5%. This regional pattern should be affected by different sub-regional characteristics,e.g.,the continuous degradationof grassland in the southern part of the KS and the restoration of grassland in Inner Mongolia,China. 相似文献
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[目的]了解野生秦岭羚牛瘤胃产甲烷古菌的组成及其多样性。[方法]提取野生秦岭羚牛瘤胃内容物总DNA,选用产甲烷菌特异性引物Met86F和Met1340R,对总DNA进行16S rRNA特异性扩增,构建秦岭羚牛瘤胃产甲烷古菌16S rRNA克隆文库,对阳性克隆进行PCR-RFLP(限制性内切酶片段长度多态性)分析,并对HaeⅢ酶切带谱不同的菌液进行测序,构建系统发育树。[结果]根据酶切带谱分析和测序结果的不同,将随机挑取的105个阳性克隆归为14个不同的可操作分类单元(OTUs)。系统发育分析表明,这些克隆序列均位于广域古菌门(Euryarchaeota),隶属甲烷杆菌科(Methanobacteriaceae,65.71%)、Methanomassiliicoccus(29.52%)和Methanosarcinaceae(4.76%)3个科。其中有57个序列与可培养菌相似度在97%以上,分属于Methanobrevibacter millerae、Methanobrevibacter olleyae和Methanobrevibacter thaueri。其余48个序列与未培养菌相似度较高,占11个OTUs。[结论]野生秦岭羚牛瘤胃产甲烷古菌多样性比较丰富,且可能存在新的分类单元。 相似文献
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内蒙古阿尔巴斯绒山羊毛囊结构及形态发生过程研究 总被引：5，自引：4，他引：5
【目的】了解绒山羊毛囊的组织结构及毛囊形态发生变化过程，为研究绒山羊绒毛发育的分子调控机理奠定组织学基础。【方法】制作内蒙古阿尔巴斯绒山羊胚胎皮肤组织切片，显微镜下观察照相。【结果】绒山羊的毛囊结构同其它动物一样，由毛球、连接组织鞘、外根鞘、内根鞘和毛干几部分组成。在胎龄55～65 d毛囊开始发生形成毛芽；胎龄135 d，大多数初级毛囊和一部分次级毛囊发育基本成熟；次级毛囊是初级毛囊的一个分支。【结论】了解了绒山羊毛囊的结构组成及毛囊从发生到发育成熟的整个形态变化过程，为相关领域研究者提供借鉴。 相似文献
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【目的】采用荧光染色标记细菌（fluorescence labeled bacteria,FLB）技术,研究山羊瘤胃中原虫对细菌的吞噬速率。【方法】利用4只装有永久性瘤胃瘘管的徐淮山羊,采集瘤胃液以获取瘤胃原虫和细菌。试验设置清洗原虫祛除瘤胃自由细菌的荧光全标组（WFLB）及未清洗原虫保留瘤胃自由细菌荧光标记组（FLB）。【结果】WFLB组和FLB组的吞噬速率分别为398.4 cells/(cell•h)和230.4 cells/(cell•h),换算为细菌N为：2.15 pg N/(cell•h)/和1.24 pg N/(cell•h)。【结论】每天每头羊由原虫在瘤胃内循环中带出的细菌N损失在WFLB组和FLB组分别估计为103.2 mg N/(d•头)、59.5 mg N/(d•头),或者细菌蛋白损失为0.645 g/(d•头)和0.372 g/(d•头)。结果同时表明,荧光染色标记技术可以应用于瘤胃原虫对细菌吞噬速率的研究。 相似文献
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[目的]比较舍饲和放牧补饲条件下济宁青山羊妊娠母羊的繁殖性能。[方法]分别研究舍饲和放牧补饲条件下青山羊妊娠母羊平均产羔率及产后发情率、羔羊初生重和断奶成活率,分析不同饲养方式对青山羊妊娠母羊繁殖性能的影响,探讨适宜的饲喂方式。[结果]养殖方式和营养水平对济宁青山羊发情率、受胎率和产羔率没有显著影响。由于舍饲和放牧补饲造成的管理和营养水平差异,舍饲组羔羊初生重和断奶成活率比放牧补饲分别提高10.7%和17.1%,表明饲养方式是影响济宁青山羊妊娠母羊繁殖性能的主要因素。[结论]可以通过改善饲养管理水平来提高母羊繁殖性能和羔羊成活率,从而进一步提高养殖效益,促进济宁青山羊规模养殖的发展。 相似文献
17.
《农业科学学报》2016,(10)
Quorum sensing(QS) is a type of microbe-microbe communication system that is widespread among the microbial world, particularly among microorganisms that are symbiotic with plants and animals. Thereby, the cell-cell signalling is likely to occur in an anaerobic rumen environment, which is a complex microbial ecosystem. In this study, using six ruminally fistulated Liuyang black goats as experimental animals, we aimed to detect the activity of quorum sensing autoinducers(AI) both in vivo and in vitro and to clone the lux S gene that encoded autoinducer-2(AI-2) synthase of microbial samples that were collected from the rumen of goats. Neutral detergent fiber(NDF) and soluble starch were the two types of substrates that were used for in vitro fermentation. The fermented fluid samples were collected at 0, 2, 4, 6, 8, 12, 24, 36, and 48 h of incubation. The acyl-homoserine lactones(AHLs) activity was determined using gas chromatography-mass spectrometer(GC-MS) analysis. However, none of the rumen fluid extracts that were collected from the goat rumen showed the same or similar fragmentation pattern to AHLs standards. Meanwhile, the AI-2 activity, assayed using a Vibrio harveyi BB170 bioassay, was negative in all samples that were collected from the goat rumen and from in vitro fermentation fluids. Our results indicated that the activities of AHLs and AI-2 were not detected in the ruminal contents from six goats and in ruminal fluids obtained from in vitro fermentation at different sampling time-points. However, the homologues of lux S in Prevotella ruminicola were cloned from in vivo and in vitro ruminal fluids. We concluded that AHLs and AI-2 could not be detected in in vivo and in vitro ruminal fluids of goats using the current detection techniques under current dietary conditions. However, the microbes that inhabited the goat rumen had the potential ability to secrete AI-2 signaling molecules and to communicate with each other via AI-2-mediated QS because of the presence of lux S. 相似文献
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[目的]探寻大蒜氧化物对山羊活体瘤胃平滑肌运动的影响,为反刍动物瘤胃代谢调控提供理论基础。[方法]选取4只健康的成年山羊为试验动物,手术安装永久性瘤胃瘘管。通过瘤胃瘘管给山羊填喂大蒜氧化物,并采用自制的活体瘤胃平滑肌运动检测装置,对山羊瘤胃平滑肌活动的变化进行检测。[结果]与对照期相比,4只试验期山羊瘤胃平滑肌收缩强度平均提高56.1%,差异极显著（P〈0.01）;瘤胃平滑肌收缩频率平均提高24.6%,差异极显著（P〈0.01）;瘤胃平滑肌收缩持续时间平均缩短19.1%,差异极显著（P〈0.01）;山羊采食量平均增加8.1%,差异极显著（P〈0.01）。[结论]大蒜氧化物能够显著增强山羊瘤胃平滑肌运动,促进瘤胃排空。 相似文献
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采用CTAB法和蛋白酶K法提取黄淮白山羊瘤胃微生物总DNA,酶切获得DNA片段,大小为23～50 kb,以E.coli EPI300为宿主细胞,构建瘤胃微生物宏基因Fosmid文库。研究发现该文库共获得克隆28 800个,插入片段大小约35 kb,空载率小于2%,容量1 008 Mb。通过羧甲基纤维素酶和木聚糖酶(Xylanase)活性筛选,分别获得具有两种酶活性的阳性克隆60和32个,木聚糖酶和羧甲基纤维素酶(CMC,Carboxymethyl cellulase)共同作用阳性克隆15个。通过已测序MF3木聚糖酶阳性克隆酶学活性分析,该木聚糖酶在最适应pH 4.5, 40℃条件下,酶活力为79.287μ·mL~(-1)。为进一步研究黄淮白山羊瘤胃内纤维素酶(Cellulase)基因奠定基础。 相似文献